Sammy has always been very selective in only letting me pet and hold her. If anyone else tried, she would bite them viciously! I knew something was special about Maddie when Sammy met her for the first time and didn't try to peck her skin off.
After two years of Sammy warming up to Maddie, Sammy performed the ultimate "I'm comfortable with you" move: Climbing into your shirt and poking her head out of your collar.
Yes, it was dark and yes, Maddie was wearing my hoodie (so it probably smelled like me). Sammy went right in the hoodie and poked her head out. We went for our walk and Sammy hung out there the entire time, happily watching the world go by.